class Time:
    '''A mutable time representation.

    This is really just a simple, mutable replacement for datetime
    that we use in the calculation of `next`.
    '''
    def __init__(self,
                 year,
                 month,
                 day,
                 hour,
                 minute):
        self.year = year
        self.month = month
        self.day = day
        self.hour = hour
        self.minute = minute
